New weather-surveillance capabilities for NSSL's phased-array radar

The U.S. Government operates seven distinct radar networks providing weather and aircraft surveillance for public weather services, air traffic control, and homeland defense. A next-generation, multifunction phased array radar (MPAR) concept has been proposed that could provide enhanced weather and aircraft surveillance services with potentially lower life-cycle costs than multiple single-function radar networks. As critical technology costs decrease, MPAR radars could prove to be a cost-effective alternative to current surveillance radars. Because the total number of required radars would be reduced, maintenance and logistics infrastructure would be simplified. The National Weather Radar Testbed Phased-Array Radar (NWRT PAR) is an S-band phased-array radar located in Norman, Oklahoma that was established to demonstrate the MPAR concept. Since its inception, a team of scientists and engineers at the National Severe Storms Laboratory (NSSL) has been enhancing the functionality of this system to bring it up to operational weather-radar standards (such as those in the operational NEXRAD network) and, more importantly, to demonstrate new capabilities in the context of weather and multifunction observations. Unlike conventional radars, which are constrained by inertial limitations of mechanical scanning, the NWRT PAR can exploit electronic beam steering to focus weather observations solely on areas of interest without having to collect data contiguously. This capability, termed adaptive focused observations, produces higher temporal resolution data without sacrificing data quality or spatial resolution through more efficient use of radar resources. This paper presents an overview of the latest improvements to the adaptive weather-surveillance capabilities of the NWRT PAR. Improvements are illustrated using data cases collected with this unique radar, which continues to provide researchers and forecasters with an effective platform for demonstrating and evaluating the MPAR concept.